Hand-operated luggage carts and shopping carts (push carts) have been widely used in airports, train stations, shopping centers and other commercial complexes. In airports, luggage carts have become very popular by travelers transporting luggage to and from planes and ground transportation. A large public airport (or another facility) requires hundreds or thousands of carts to satisfy the demands of travelers. Luggage carts may also become a nuisance at the airport since many customers do not return the carts to a collection area after using them. Unreturned carts can even be a safety hazard to pedestrian and motor traffic.
Furthermore, if there are many escalators, it is very convenient if a person using the cart can move up or down on the escalator together with the cart. However, in a middle section of the escalator, the inclination creates a large level or height difference between adjacent steps. Therefore, the cart located on an inclined section of the escalator tends to move due to the forces of gravity. The cart may move with respect to the escalator and fall. The movement of the cart is difficult to avoid given the inclined structure of the escalator. However, various designs for carts suitable for escalators have been provided in U.S. Pat. Nos. 5,516,127, 6,126,176; and 6,131,936, all of which are incorporated by reference.
Shopping carts have also become necessary items of equipment for large modern stores and supermarkets. A shopper utilizes a shopping cart to transport items to be purchased. Then, a shopper passes a shopping cart through a checkout stand carrying purchased goods to a vehicle parked at the exterior of the market or mall. Unfortunately, many shopping carts are damaged in the process and at a parking area, or are stolen therefrom.
There are several theft prevention systems described in U.S. Pat. Nos. 3,002,370; 3,475,036; 3,590,962; 3,394,945; 3,892,295; 4,524,985; 4,577,880; 4,772,880; 4,868,544; 5,194,844; and 5,432,412 all of which are incorporated by reference.
Due to the nature of use and the large number of luggage carts used at airports, and shopping carts at modern malls and supermarkets, there is a need to locate the carts. Furthermore, there is a need to maintain properly the carts to prevent their break down (and even possible injuries caused by a cart break down).